- From: Dan Connolly <connolly@w3.org>
- Date: 22 Apr 2002 16:19:32 -0500
- To: Jonathan Borden <jonathan@openhealth.org>
- Cc: "Peter F. "Patel-Schneider <pfps@research.bell-labs.com>, Jeremy Carroll <jjc@hplb.hpl.hp.com>, www-webont-wg@w3.org
On Mon, 2002-04-22 at 15:56, Jonathan Borden wrote: [...] > "Patients with a dominantly inherited disease have a father with a > dominantly inherited disease, and/or a mother with a dominantly inherited > disease" > > <Class rdf:ID="DominantInheritance"> > <unionOf> > <Restriction> > <onProperty rdf:resource="#mother"/> > <toClass rdf:resource="#DominantInheritance" /> > </Restriction> > <Restriction> > <onProperty rdf:resource="#father"/> > <toClass rdf:resource="#DominantInheritance" /> > </Restriction> > </unionOf> > </Class>] > > ... OK; that looks like a stumper: it's a defined class, and it's circular. I doubt Jeremy's rules provide for the relevant conclusions. (Jos? wanna give it a try with Euler?) I can now see how the theoretical question relates to real-world problems. Thanks. At a glance, I'm pretty sure I could live with a theory of classes that was too weak to deal with that thing, at least for a few years. But I'll have to mull it over. Some details... > Dan Connolly wrote: > > > > > Er... that's begging the question. No fair. > > Actually, "begging the question" has a different logical meaning than you > intend here, Ummm... I looked it up. http://datanation.com/fallacies/begging.htm The question was: why do we need circular stuff to exist? You answered it by saying "suppose some circular stuff exists...". That's not begging the question? I thought I was getting the hang of these things. > but that is a different matter. OK... > > I don't expect cyclic structures to come up in normal stuff at all. > > > > Please explain why you think cyclic structures will be necessary > > to define (?) a disease. > > something like one of these (simplified for example purposes): > > "Patients with a paternally inherited dominant disease, have fathers with a > paternally inherited dominant disease" > > (note, for "patients with ..." read "patients who are members of the class > of people with ...") > > <Restriction rdf:ID="PaternalDominantInheritance"> > <onProperty rdf:resource="#father"> > <toClass rdf:resource="#PaternalDominantInheritance"> > </Restriction> I don't think that's what you meant. That says that PaternalDominantInheritance is *exactly* those things whose fathers have type PaternalDominantInheritance; that there are no other conditions (like actually having a disease) for being in this class. I think you meant that PaternalDominantInheritance is a *subClass* of the (father hasClass PaternalDominantInheritance) restriction, right? OK, that's still circular, but it's a "primitive" class; i.e. you're going to be able to communicate to the machine *necessary* conditions for being in this class, but not *sufficient* condidions, right? > "Patients with a maternally inherited dominant disease, have mothers with a > maternally inherited dominant disease" > > <Restriction rdf:ID="MaternalDominantInheritance"> > <onProperty rdf:resource="#mother"/> > <toClass rdf:resource="#MaternalDominantInheritance"/> > </Restriction> > > "Patients with a dominantly inherited disease have a father with a > dominantly inherited disease, and/or a mother with a dominantly inherited > disease" > > <Class rdf:ID="DominantInheritance"> > <unionOf> > <Restriction> > <onProperty rdf:resource="#mother"/> > <toClass rdf:resource="#DominantInheritance" /> > </Restriction> > <Restriction> > <onProperty rdf:resource="#father"/> > <toClass rdf:resource="#DominantInheritance" /> > </Restriction> > </unionOf> > </Class>] > > ... -- Dan Connolly, W3C http://www.w3.org/People/Connolly/
Received on Monday, 22 April 2002 17:20:40 UTC